Behaviour and Biology
It's unpleasant to realize that your home may have cockroaches but cockroaches can get into the cleanest places because we often bring them home without even knowing it. They can travel on your breifcase from work or a bag from a store. They can crawl through tiny spaces, for example, gaps around doors. Cockroaches typically seek warmth, moisture and darkness (they are nocturnal) but they also will enjoy any leftover food particles as an added bonus.
If you’re finding cockroaches, chances are there’s a food source in your kitchen, storage area, bathroom, utility room or maybe in the room or suite next to where you spotted them.
Tell tale signs you have cockroaches is through visual sightings (for example, you might walk into your kitchen for a midnight snack, and see them scatter about once you turn on the lights); noticing their fecal matter (i.e. little black spots in the cupboards that look like pepper) or their egg capsules (known as “ootheca”) which are yellowish brown in colour, and rectangular in shape.
The most common cockroach you might encounter is the German cockroach, which is light brown to tan in colour, and about ½” to 5/8” (13-16mm) in length. You might notice various sizes of cockroaches, which many people refer to as “baby” cockroaches, which in fact, are the nymphs. Once born, cockroaches will go through several growth spurts (instars) in their nymphal stage before they reach adult size. Lastly, another indication that you have cockroaches is the odour that is prevalent when these insects invade your residence or commercial establishment. This odour comes from the secretions that roaches leave behind, that end up on surfaces such as plates, utensils or food items.
Some other types of cockroaches that have been identified in the Lower Mainland include American and Oriental cockroaches, which are similar in behaviour to the German cockroach.
There are several risks associated with cockroaches, the most obvious being the fact that they carry numerous types of diseases. Some of the more common disease pathogens (specifically bacteria, protozoans and viruses) associated with cockroaches include Salmonella (food poisoning), Staphylococcus, Streptococcus, Coliform, Bacillus, Clostridium, Escherchia coli (diarrhea), cholera, plague and polio. Cockroaches can also cause allergic reactions and even asthma.
If you manage or own a restaurant, retail food establishment, food distribution warehouse or food processing plant, you run the risk of being shut down by health officials, or having to dispose of your inventory if it’s cockroach infested, resulting in the loss of hundreds or thousand of dollars in lost revenue or product cost. If the public happens to notice cockroaches in your establishment or product, you run the risk of never having clients dine/shop at your establishment, and more importantly, they will let all their friends and family know about their traumatic experience, jeopardizing the reputation of your brand.
The key to controlling cockroaches involves following the following five steps:
Inspecting product or merchandise before it enters your kitchen, restaurant, food distribution or food-processing plant is a great start in controlling any existing or potential cockroach infestations. Landlords and building managers need also be aware of tenants bringing items into homes that may be cockroach infested, such as microwaves, toasters, coffee makers, food storage containers and any electronic equipment.
It goes without saying that thorough cleaning, especially behind major appliances and in the backs of cupboards is absolutely necessary for cockroach control. Regular cleaning needs to be maintained to minimize the food, water and harbourage that’s available for cockroaches (and any other insect for that matter), putting stress on the population and making it difficult for them to survive.
Knowing where cockroaches are harbouring is important as it will determine where cleaning and/or treatment is necessary. Inspection can include a simple visual inspection using a flashlight to a monitoring program implemented by a professional IPM technician.
4. Insecticide Application
There have been significant advancements in cockroach treatment techniques. Insecticide bait is the preferred method of choice, and does not require people or pets to leave the premises. There are several types of commercial bait available to commercial applicators, and any bait applied is always applied in accordance to the label. For an effective baiting program, proper sanitation must be initiated and maintained by the home owner, restaurant, facility, processing or warehouse manager.
For commercial establishments, the risk of reintroduction is high given that new inventory is constantly entering your premises, and the source of the roaches could be coming from any of your suppliers. Maintenance involves a commercial technician regularly inspecting and monitoring existing or potential cockroach populations. Proper documentation and logging will determine when and if treatments are necessary, as well as include sanitation or prevention recommendations.